It is widely known that the late, great Pop artist Roy Lichtenstein sourced much of his imagery from comic books and newspaper comic sections of yore, tweaking the scale to create the boldly painted compositions that made him world famous. But rarely do the collectors who pay millions for his paintings spare a thought for the Ben-Day artists who inspired his work.

This was likely the case last week at Christie’s when Lichtenstein’s classic bubble-captioned painting “I Can See The Whole Room!... And There’s Nobody In It!” sold for an artist-record $43,202,500 to New York private dealer Guy Bennett. The cover lot last sold at auction at the same house, also as the cover lot, in November 1988 for a then-dazzling $2,090,000 (est. $800,000-1.2 million), part of the fabled Tremaine Collection. The Connecticut-based Burton and Emily Tremaine, for their part, had acquired the work from the Leo Castelli Gallery in November 1961 — the year it was painted — for a discounted price of $450, according to gallery records provided by Barbara Castelli, the late dealer’s widow who continues to run the gallery.

Christie’s academically styled catalogue entry included a reproduction of the source image for the painting, culled from an August 6, 1961, panel of Saunders & Overgard’s syndicated comic “Steve Roper.” Apart from the word “Trooper!”, which began the bubble caption in the original, the text and image are virtually identical. Of course, the newspaper strip was black and white, and Lichtenstein added a yellow background to further dramatize the blown-up, sharply chiseled male visage staring through the peephole.

But there’s more to the story than a polite footnote about the Steve Roper source material.

In 1963 the painting was exhibited in the Guggenheim’s landmark exhibition “Six Painters and the Object.” Lichtenstein, then 39, had just been featured in a splashy Time magazine piece about the new Pop art craze, which included a comment about his use of real comic strips as models: “there is enough change so that he can claim to impose his own order on them.” A published letter to the editor by William Overgard, the then-36-year-old cartoonist and creator of the original drawing, followed.

“Sir: As a cartoonist, I was interested in Roy Lichtenstein’s comments on comic strips in your article on pop art,” went the letter. “Though he may not, as he says, copy them exactly, Lichtenstein in his painting currently being shown at the Guggenheim comes pretty close to the last panel of my Steve Roper Sunday page of August 6, 1961. Very flattering… I think?”

Overgard, the son of a silent movie star and a published author and screenwriter in the science fiction and horror film realm, died in 1990 at his 17-acre farm in Stony Point, New York. You might say Overgard had his Warholian 15 minutes of fame, but there’s also more to his legacy than that.

The cartoon artist was tracked and rediscovered in part by David Barsalou, the creator of the Web site Deconstructing Roy Lichtenstein, a three-decade endeavor to track down the original cartoons that the Pop art icon supped on.

“A lot of these major collectors, they want a Lichteinstein, which is fine,” Barsalou said in a phone interview, “but the whole premise of Deconstructing Roy Lichtenstein over the years is just to bring recognition to the original comic art that Lichtenstein copied.”

“If these collectors understood the intrinsic value of original comic art they’d be grabbing all of that stuff because its at bargain prices right now,” continued Barsalou, who studied Pop art as a student in the late ‘70s at the Hartford Art School. “Sooner or later the art world is going to catch up to it.”

Barsalou has his own auction story to tell, in fact, tying the frayed thread between Overgard and Lichtenstein. Last August, the cartoon aficionado found the original Overgard panel on eBay and outdueled four other remote bidders to snag the prize for $431. Overgard had donated his 3,000-plus cartoon archive to the Special Collections Research Center at Syracuse University, but that panel is not part of that protected trove.

“To me,” said Barsalou, “it was the steal of the century.”